Propeller



A. SCHERTZ Aug. 20, 1929.

1929 2 Sheets-Sheet 3 Adolph Scheri'z v A iiorney Au 20, 1929. A. SCHERTZ 1,725,482

PROPELLER Filed Jan. 4, 1929 -2 ShGBtS-Sheet 2 1n ventor {idol oh Scherfz Attorney Patented Aug.-- 20, 1929.

UNITED STATES PATENT OFFICE.

AlDOLPE SOHERTZ, OF YOUNGSTOWN, OHIO.

PROPELLER Application filed January 4, 1929. Serial No. 380,308.

The present invention relates to ropellers of a type adapted particularly or use upon aero lanes, but which also embodies features w ich permits of the propeller in driving ships and for other purposes where propellers of this character are employed.

One of the important objects of the mvention is to provide a propeller embodying a pluralit of blades having the leading or forward e ge thereofrolled in a manner whereby to create a'vacuum upon the forward surface of the blade to counteract any pressure encountered during the forward movement of the propeller through the air or water.

A further object of the invention is to provide reinforcing ribs for each of the propeller blades arranged in a manner to strengthen the blades and at the same time to offer no added resistance during the operation of the propeller.

A still further object of the invention is the invention as more fully hereinafter de-' scribed and claimed, reference being bad to the accompanying drawings forming part hereof wherein like numerals refer to like parts throughout, and in which:

Figure 1 is'a front elevational view,

Figure 2 is a rear elevational view,

Figure 3 is an elevational view looking toward the leading or forward edge of one of the blades,

Figures 4 and 5 are transverse sectional views through one of the blades, taken respectively along the lines 44 and 5-5 of Figure 1, i

Figure 6 is a transverse sectional view through the center of'the propeller, and

Figure 7 is a fragmentary tive view of the end ofone of the b ades illustrating the pocket formed on the forward face of the blade by the rolled leading edge thereof.

Referring to the drawings in detail for the purpose of illustration, I have illustrated a practical form of the invention which embodies a hub 5 having a bore 6 extending therethrough adapted for receiving the end of a propeller shaft for driving the propeller in the usual manner well known in the art.

A plurality of propeller blades 7 extend tangentially with respect to the hub, the present embodiment of the invention illustrating the propeller equipped with four of such 1 that the propeller may embody any desired number of blades to produce more eflicient results under certain conditions.

- The trailing edge of each blade, indicatedat 8 extends radially from the axis of the hub and are arranged so that the trailing edge of the blades at the opposite side of the pro eller are disposed in alinement'at diametrically opposite sides of the hub.

ades, it being understood however The leading or forward edge of each of V the blades indicated at 9 is of an arcuate formation as clearly illustrated in Figures 1 and 2 of the drawings and are formed with a rolled edge 10 extendin forwardly of the front surface of the bla e and likeof the leading edge of the blade.

The inner end of the are formed by the rolled edge 10 passes through the axis ofthe hub 5, as more clearly shown in- Figure 1 of the drawing whereas the outer end of said arc merges with the are formed by the leading edge 9 inwardly of the extreme outer end of the blade.

A rib 11 extends longitudinally of each of the blades and is disposed upon the forward surface thereof whereby to form a longitudinally extending trough 12 in the rear surface of the blade. The r-ib 11 is likewise of an arcuate formation with its inner end passing through the axis of the hub and its outer end merging with the outer end of the rolled edge 10.

The area of the front surface of each of the blades, between the leading edge 9 and the rib 11 is thus formed into a pocket 13. As more clearl illustrated in Fi res 4 and 5 of the draw1ngs,.the forward ace of the blade within which the pocket is formed, is concaved as shown at 14, the rear surface of this portion of the blade being likewise convexe The area of the blade between the rib 11 wise formed in an arc eccentric to the are I versely extending ribs 15 extending toward each edge of the blades from the ribs 11, the ribs 15 being likewise of a slightly arcuate formation eccentric with respect to the hub. The hub at the forward side of the propeller isexternally threaded for receiving a .cap 16 secured in position upon the hub against accidental displacement by the set screws 17.

By reason of the pocket 13 formed in the.

forward surface of each of the blades an air pocket will be created tending to counteract pressure against the forward side of the lade exerted against the propeller as the same moves forwardly.

Also by reason of the arcuate formation of the leading or forward edges of the blade less resistance will be offered thereto as the propeller is rotated.

It will further be apparent that the IlbS 15 materially strengthen the blade and maintain the respective plane and concaved surfaces thereof against distortion during the rapid rotation of the propeller, thus by reason of the arcuate formation of these ribs it I v will be apparent that the same offer no addedge of the blade and extendin ed resistance to the air or water through which the blades are passing.

It is obvious that my invention is susceptible to various changes and modifications in construction without departing from the spirit of the invention or the scope-of the appended claims, and I accordingly claim all such forms of the device to which I am entitled.

Having thus described my invention, what I claim as new is:

1. A propeller comprisin a hub and a plurality of blades exten ing outwardly therefrom with the trailing edges of the oppositely disposed blades arranged in alinement and with .a lip formed at the leadin forwardly over the front surface of the b ade.

2. A propeller comprising a hub and a plurality of blades exten ing outwardly therefrom with the trailing. edges of the op positely disposed blades arranged in alinement and with a lip formed at the leading edge of the blade and extending forwardly over the front surface of the blade, said lip of each of the blades likewise being arcuately formed and disposed eccentrically with respect to the arc of the respective leading edges and merging with the leading edges inwardly of the outer ends of the blades.

3. A propeller comprising a hub, a plurality of blades extending outwardly therefrom with the trailing edges of the oppositely disposed blades arranged in alinement and with a lip formed at the leading edge of the blades and extending forwardly over the front surface of the blades, said lip of each of the blades likewise being arcuately formed and disposed eccentrically with respect to the arc of the respective leading edges and merging with the leading edges inwardly of the outer ends of the bladesv and a rib extending longitudinally of each of the blades with the area of the blade rearwardly of said ribs having a plane surface and the area of the front surface of the blade forwardly of the rib concavedwhereby to form a pocket between the lip of theblade and the rib.

4. A propeller comprising a hub, a plurality of blades extending outwardly therefrom with the trailing edges of the oppositely disposed blades arranged in alinement and with a lip formed at the leading edge of the .blades and extending forwardly over the front surface of the blades, said lip of each of the blades likewise being arcuately formed and disposed eccentrically with respect to the arc of the respective leading edges and merging with the leading edges inwardly of the outer ends of the blades and a rib extending longitudinally of each of the blades with the area of-the blade rearwardlv of said ribs having a plane surface and the area of the front surface of the blade forwardly of the rib concaved whereby to form a pocket between the lip of the blade and the rib, said rib also being arcuately shaped and disposed eccentrically with re spect to the lip and leading edge and merging at its outer end with the outer end of said lip.

5. A propeller comprising a hub, a plurality of blades extending outwardly therefrom with the trailing edges of the oppositely disposed blades and with a lip formed at the leading edge of the blades and extending forwardly over the front surface of the blades, said lip of each of the blades likewise being arcuately g formed and disposed eccentrically with re- I spect to the arc of the respective leading edges and merging with the leading edge inwardly of the outer ends of the blades arranged in alinement and a rib extending longitudinally of each 4 of the" blades with .the area of the blade rearwardly of said ribs having a plane surface and the area of the front surface of the blade forwardly of the rib concaved whereby to form a pocket between the lip of the blade and the rib, said rib also being arcuately shaped and disposed eccentrically with respect to the lip and leading edge and merging at its outer end with the outer end of said rolled edge, and said rib and said lip having their inner ends terminating at the axis of the hub.

6. A propellercomprising a hub, a plurality of blades extending outwardly therefrom with the trailing edges of the oppositel disposed blades arranged in alinement an with a lip formed at the leading edge of the blades and extending forwardly over the front surface of the blades, said lip of each of the blades likewise being arcuately formed and disposed eccentrically with respect to the arc of the respective leading edges and merging with the leading edges inwardly of the outer ends of the blades and a rib extending longitudinally of each of the blades with the area of the blade rearwardly of said ribs having a plane surface and the area of the front surface of the blade forwardly of the rib concaved whereby to form a pocket between the li of the blade and the rib, said rib also being arcuately shaped and disposed'eccentrically with respect to the lip and leading edge and merging at its outer end with the outer end of said lip, and said rib and said lip having their inner ends terminating at the axis of the hub, said plane surface of the blade being of an increased Width toward the outer end of the .blade and arranged with the trailing edge ity of blades extending outwardly therefrom with the trailing edges of the oppositely disposed blades arranged in alinement and with a lip formed at the leading edge of the blades and extending forwardly over the front surface of the blades, said lip of each of the blades likewise being arcuately formed and disposed eccentrically with respect to the arc of the respective leading edgesand merging with the leading edges inwardly of the outer ends of the blades and a rib extending longitudinally of each of the blades with the area of the blade rearwardly of said'ribs having a plane surface and the area of the front surface of the blade forwardly of the rib concaved whereby to form a pocket between the lip of the blade and the rib, said rib also being arcuately shaped and disposed eccentrically with respect to the lip and leading edge and mergin at its outer end with the outer end of sai and said lip having their inner ends terminating at the axis of the hub, said plane surface of the blade being of an increased width toward the outer end of the blade and arranged with the trailing edge thereof inclined rearwardly and outwardly, and a plurality of arcuately shaped reinforcing ribs. formed on each surface of the blade and disposed eccentrically with respect to the hub.

. In testimony whereof I afiix my signature.

ADOLPH SCHERTZ.

lip, and said rib 

